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For the Teacher
• Students will learn the basics of osmosis and diffusion and understanding how it
affects plants under different conditions
• Students will be able to explain and discuss the different solutions a plant could
be exposed to and the result of such solution
Prior to starting an experiment on osmosis using gummy bears ask a few critical
thinking questions/ check for understanding. Have them write in a blank piece of
paper and turn it in to you to see if they truly understand what's been discussed.
Standards:
G. Plant and Soil Science Pathway
G.2.0
G2.2
What we will accomplish today…
• Understand the process of osmosis
and diffusion
• Be able to explain the effect of
osmosis in plants with different
solutions
• Hypotonic
• Hypertonic
• Isotonic
Osmosis
Process in which a solute passes through a semipermeable membrane.
Other
Molecule
High
Low
H20
A solute is a part of a solution which dissolves.
A semipermeable membrane is like a wall on
the cell that blocks some molecules and allows
others in
The solute travels from an area of high
concentration to an area with low concentration.
This process of
moving from high to
low concentration is
called diffusion
Hypotonic State: a state in which there are less
solute molecules outside the cell. This causes wate
to move into the cell and that object will expand
Isotonic state: a
solution with an equal concentration to
another solution.
How does this apply to Plants?
Plants use osmosis to absorb water and nutrients from the soil.
What will happen to a plant in Hypertonic
Solution?
Discuss with a partner.
In a hypertonic solution a plant will shrivel up.
• Water inside the cells is drawn out
• Vacuoles and Cytoplasm shrink in
size
This causes a lack of structure
What will happen to a plant in Hypotonic
Solution?
Discuss with a partner.
In a hypotonic solution a plants cells will fill up
to maximum capacity.
• A strong cell wall stops the cells
from bursting
• The plant will become turgid
What will happen to a plant in an isotonic
solution?
Discuss with a partner?
In an Isotonic solution the plant will remain in
equilibrium.
• Nothing will happen
• No movement of water into or
out of the cell
Next week we will do an experiment on osmosis
for Understanding:
Via to
thediscuss
Gummy
usingChecking
gummy bears
Lets take some time
Family
what we believe wouldBear
happen
to these gummy
bears?
Momma Bear is in a
solution of water
Papa Bear is in a
solution of Salt Water
Baby Bear is in a solution
of distilled water
Gummy bears have a very low concentration
of H2O
Momma Gummy Bear has been placed in a
cup of water
What will happen to momma gummy bear
and why?
Once again gummy bears have a very low
concentration of H2O
Papa Gummy Bear has been placed in a cup
of salt water.
Hint: Salt molecules are much smaller then
the molecules in the gelatin.
Where are the highest concentrations of
solute?
What will happen to papa gummy bear and
why?
By now you should know that gummy bears
have a very low concentration of H2O
Baby Gummy Bear has been placed in a cup
of distilled water
Distilled water is pure water with no
impurities.
What will happen to baby gummy bear and
why?